In a move that could free up backpack space on college campuses nationwide, Amazon is reportedly looking to enter the school textbook market with the release of a new, student-friendly version of its Kindle electronic book reader. The Seattle Post-Intelligencer quotes a McAdams Wright Ragen analyst as saying that the company is already at work on new Kindles and sees an opportunity in the $5.5 billion textbook market. Amazon has previously confirmed that there will be Kindle updates but isn’t commenting on targeting specific markets.